Printing telegraph apparatus



Oct. 19, 1943. J, Z NN R 2,331,952-

PRINTING TELEGRAPH APPARATU S Filed Nov. 6, 1941 2 Sheets-Sheet 1INVENTOR.

WALTER J. ZENNER m B Y c DLC H 'A' ORNEY,

Oct. 19, 1943. w. J. ZENNER 2,331,952

PRINTING TELEGRAPH APPARATUS Filed Nov. 6, 1941 2 Sheets-Sheet 2 FIG.4 4

INVENTOR. WALTER J. ZENNER A ORNE-Y.

Patented Oct. 19, 1943 PRINTING TELEGRAPH APPARATUS Walter J. Zenner,Des Plaines, 111. assignor to Teletype Corporation, Chicago, 111., acorporation of Delaware Application November 6, 1941, Serial No. 418,009

Claims.

The present invention relates to prihting telegraph apparatus and moreparticularly to recomers responsive to iso'chron'ous code signals havinga single Selective current impulse.

The principal object of the present invention is to provide all emeientage printer of Simple construction operable upon the start-Stopprincipls and comprising a minimum Of operating par A feature of theinvention is to provide a page printing apparatus having a singleselector magnet which controls a cam printing mechanism to produce aprinted record in response to equal length code signals, each composedof two elements of o posite signaling characteristics whose individualtime intervals are variable but complementary, so that their summationin each code signal is equal to a predetermined time con- 's'tant.

In accordance with the present invention, the line signal for eachcharacter consists of a nocurrent starting impulse and a currentdefinitive impulse. in the event that signal elements of oppositepolarity are employed. the starting irn= pulse will be of positive ornegative current, and the definitive impulse will be of negative orpositive nature, respectively. Specifically, each code signal iscomposed of two signal elements in which each signal element occurs butonce in a code signal. elements in each node signal is constant, and a1though each element varies in length, nevertheless each element in eachcode signal is the coinelement of the other element of that particularcode signal. Hence, each signal is formed and each character isdetermined by the relative length of the elements composing the codesignal.

Upon the reception of the starting impulse, a selector magnet, which isnormally energized since the idle condition or the line is of marking orcurrent nature, releases its armature to control a power clutch; thuspermitting a type wheel to rotate, in phase with a controlling elementin 'a remote transmitter. During the rotation of the type wheel; theselector magnet, upon deter mination of a starting impulse which occurssi-- muItaneQusI with thebgiiihihg of the definitive impulse of oppositepolarity or current condition, again becomes energized and attracts andoperates its armature, which action serves, in the preferred form of theinvention, to actuate a cam printing mechanism to efiect printing at theinstant when the reversal or signaling condition occurs in the onesignal cycle. In

The sum or the lengths of the other words, the receiving magnet, upon areversal of signaling conditions, during the rotation of the type wheel,which occurs at the termination of the starting impulse and thebeginning of the contiguous definitive impulse, attracts its armatureand causes a printing hammer to operate to print a character. Afterprinting has been effected, the type wheel is released and continues torotate and is stopped as it completes one revolution.

A better understanding of the invention may be had from the followingdescription taken in conjunction with the accompanying drawings, whereinlike reference characters designate similar parts throughout the severalviews, and in which,

Fig. 1 is a graphical representation of the type of the code signalemployed in operating the printer according to the present invention;

Fig. 2 is a perspective view of the printer, viewing the structure fromone side thereof;

Fig. 3 is a perspective view of the printer, viewing it from theopposite side;

Fig. 4 is a side elevation of the printer showing the characterselecting mechanism;

Fig. 5 is a side elevation of the printer showing the character spacingand line feeding function mechanism, and

Fig. 6 is a cross-sectional view of the printer showing the type wheelmechanism and the page guiding apparatus.

There is indicated in the graphical representation illustrated in Fig. 1a sequence of monopulse isochronous code signals representative ofalpha;- bet characters, for example, G and N. All code "signalsaccording to this code are of equal length, each code signal consists oftwo elements of different signaling characteristics; for em ample,current-no current, difierent potential or difierent polarity, and eachcode signal comprises only a starting condition or selecting impulse Aand a contiguous definitive condition or impulse B. The point at whichthe reversal of the current or characteristic nature of the code signaloccurs is determinative of the identity of the character to be printedand is the point at which printing is effected. The stop intervalbetween signals is indicated D in Fig. 1 and is of variable duration.

Having reference to Figs. 1 and 2, the printer structure comprises sideplates II and I2 which are mounted on a base plate l3, and are maintained in a predetermined spaced relation parablel to each other byspacer rods l4, l5, and I6 (the end only of rod [6 being shown in Fig.3).

As indicated in Figs. 2 and 3, a motor H is shown mounted on the sideplate H by means of posts l8 and i6. A third post is also provided formounting the motor H which post is not shown in the drawings. It is, ofcourse, understood that the motor I1 may, if desired, be mounted on thebasej plate l3. It is necessary that the speed of the motor at thereceiving station be regulated so that the type wheel of the printerrotates substantially in phase with a controlling element at thetransmitting station.

Upon the armature shaft 26 of the motor I1 is secured a pinion gear 2|which meshes with a drive gear 22 carried on a shaft 29 suitablyjournaled in ide plates H and I2. The gear 22 is connected to the shaft29 by means of a friction clutch comprising a pair of discs offrictional material compressed between the flange of a flanged collar 23and an indexing wheel 24. Compression is imparted to the friction clutchby a compression spring 25 positioned between the collar 23 and a nut 26screwed onto the end of shaft 29. In this manner, the shaft 29 uponwhich the type wheel 21 (Fig. 3) and indexing wheel 24 are fixed isgiven a normal urge to rotate.

A selector magnet 3| is carried by a bracket 32 mounted on the sideplate I I. An armature lever 33 is associated with magnet 3| and iscarried on a pivot shaft 34 secured to the side plate Armature lever 33is provided with an arm 35 (Fig. 4) to which is pivotally connected adepending pawl member 36. Pawl 36 cooperates with a ratchet wheel orprinting cam 31 and is normally urged into engagement with the cam teethof the printing cam 31 by means of a spring 38 distended between pawl 36and lever arm 35. The cam 31 is mounted rotatably on stud 39 fixed tothe side plate Upon the de-energization of magnet 3|, the armature 33will be released and will rotate slightly in a counterclockwisedirection about pivot 34 under the action of a spring 4| against aneccentric stop member 42, which provides an adjustable stopping meansfor the armature lever 33. As the armature lever 33 is thus released,the pawl 36 is thereby raised, so as to engage the next tooth on theratchet cam 31 so that when the armature 3| is again energized and thearmature lever 33 is attracted, pawl 36 will have downward movementimparted to it which will cause the cam 31 to be stepped one angularstep in the clockwise direction.

Associated with the cam 31 is a printing control lever 43 which ispivotally mounted on the I side plate H by means of a pivot 44. Theprinting control lever 43 is provided with an arm 45 terminating in a Vconformation whereby it cooperates with the cam teeth of the cam 31. Theprinting control lever 43 is also provided with a lug 46 whichcooperates with the notches of the indexing wheel 24. The printingcontrol lever 43 is provided with a spring distended between lever 43and a spring post on side plate I whereby arm thereon is held intocooperative engagement with the cam 31.

Pivotally supported on the pivot 44 and disposed on the inside of sideplate II is one end of the printing bail 41. the other end beingcorrepsondingly pivoted at 59 to the side plate I 2 (Fig. 2). On its armadjacent the plate H, the printing ball 41 is provided with an eccentricstop 48 (Fig. 4) which extends through an aperture in the side plate I linto cooperative relation with the printing control lever 43. In thismanner,

when the ratchet printing cam 31 is actuated stepwise to cam out theprint control lever 43 through the instrumentality of the projection 45and the lever 43 is actuated counterclockwise against the action of itsspring 46, lever 43, through the instrumentality of said eccentric stop48, will impart corresponding rotation to the printing bail 41 againstthe action of its retractile spring 49 (Fig. 3) to cause the printingbail 41 to strike against the periphery of the type wheel 21 to effectthe printing of a character upon the record material insertedtherebetween.

The armature lever 33 (Fig. 4) is provided with an extension 5| at itsfree end, which cooperates with the free end of a stop-start lever 52pivotally supported at 53 to the upper end of an orientation member 54,which is pivotally mounted at on the side plate Stop lever 52 isprovided with a lateral portion or projection 56 which is directedtoward the index wheel 24. Secured to the index wheel 24 and directedtoward the side plate H is a projecting member 51, which cooperates withthe projecting portion 56 of the stop lever 52. When the selector magnet3| is energized, and the armature lever 33 thereof is pulled in itsclockwise or attracted position against the action of its spring 4|, theend 5| depresses the free end of lever 52 and urges said lever 52 in acounterclockwise direction about its pivot 53 against the action ofspring 58 to bring the stop projection 56 into the path of the clockwiserevolvable stop lug 51. In this manner, the shaft 29 to which theindexing wheel 24 is fixed, is held against rotation, while the gear 22continues to rotate due to the friction clutch with which it iscooperatively related to shaft 29.

For orientation purposes the lever on index arm 54 may be rotated aboutits pivot 55 upon the loosening of the clamping screw 6| whereupon thestop lug 56 may be moved rightwardly or leftwardly to change thestopping position of the stop lug 51 to correspond to the reception ofthe start-stop code signals. Upon the de-energization of the selectormagnet 3|, the armature lever 33 is released and responds to its spring4| to be rotated counterclockwise against the stop 42. As the result ofthis movement, the end 5| is lifted away from the free end of the stoplever 52, which is then free to respond to the pull of its spring 58 tocause said lever 52 to rotate clockwise about its pivot 53 therebymoving the stop lug 55 out of the path of the stop lug 51, thuspermitting the shaft 29 to rotate.

Slidably mounted on the shaft 29 is the type wheel 21 (Fig. 3). Toimpart rotation to the type wheel 21, the shaft 29, between the sideplates H and I2. is of square conformation and fits into a square holein the type wheel 21. The type wheel 21 is moved along the shaft 29through the instrumentality of a U-shaped bracket 63 carried slidably onan auxiliary shaft 64. Bracket 63 is provided with a vertical arm 65(Fig. 6) which terminates in a forked end and fits into a grooveintegral with the hub of the type wheel 21, whereby as the bracket 63 ismoved along the shaft 64, as will hereinafter appear, the type wheel 21will be urged correspondingly along its shaft 29 by means of thearticulation of the arm 65 with the hub of the type wheel. Secured tothe bottom of the bracket 63 is a thin metal strip 65 which extendsupwardly and is interposed between the type wheel 21 and the printingbail 41. In registry with the printing zone, the strip 66 is suitablyapertured so as to permit printing to be effected therethrough and toprevent smudging otthe printed record. Also pivoted on the shaft 64-isabracket 61 which carries an inking rollertt thebrack et. 6! being springurged. by a spring. (not shown. but which is;wound around the. shaft 64)in suitablemanncr "to bring the inking roller 68 constantly into contactwith the peripheryotthe type wheel 21.

To accomplish the: functionof character spacing, a cable H is securedtothebracket 63; and extends around a pulley 12 (Fig; 5) carried: on abracket 13 secured to the; side plate l-2. The side plate I2 isapertured adj'acentto pulley 12 to. permit the passage or the cable Htherethrough which is then directedfrom the pulley 12 to the groove inthe periphery of a grooved pulley M which is rotatably mounted on theside plate l2 by moment a studio, Also mounted on; stud 15' and securedto. the: pulley Id-by means of the screws T6 is" a spacingratchet. 11.operating with the ratchet Tl is a pawl l'-8 which is: pivotally carriedon the extremity of the de pending arm of a. bell crank. lever 19pivoted on a common stud 81: secured to the side plate 12. Thehorizontal arm of the bell crank 19 cooperates at its extremity withalcam 2B fixed to the shaft 29. According. to the start-stop principleof operation of the printer herein described, the shaft 29 makes onerevolution for each char acter signal, and correspondingly the cam 28also makes one revolution to, operate the bell crank 19: once for eachCharacter printed. The cam 28 is shown in Fig, 5 substantially in. itsstopped position wherein it can be seen. that the spacing; operationoccurs substantially atlthe end of the printing. cycle of operation; Asthe-shaft 29 is released for rotation and the cam. 28: thus isinitiatedinto rotation, the cam 28 after traveling substantially 240begins; to rotate the bell crank lever 19 clockwise against the actionofits spring 82? thus urging. the pawl 18: leftwardly (as viewed in Fig.5) to pick up the next or following tooth of the ratchet. wheel H. Thepawl. i8 is normally urged. into. cooperative relation. with the teethon the ratchet. wheel llby aepring. 83 distended between a projection onthe .pawl lever 78 and. a projection on. the. bell crank lever it: sothat clockwise rotation, is. normally. imparted to the pawl lever 1-5;After the cam 28 has rotated substantially 360", the" bell crank. leverT9: is allowed to drop. off the high part of the cam whereby the spring82 effects the counterclockwise. rotation of lever T9 to; im-

part thereby rightward movement to the pawl 18 which will causetheratchet. wheel. 11 to rotate the pulley 1.4 step-by-step until: thetype wheel a and its carriage has reached the endzof' the line;whereupon the carriage return signal is received to. cause the typewheel to: return,. as will be presently described, to thebeginning-of-line position. Of course, it is understood that thecarriage return signal may be received at any time in the line so that afull winding of the cable ii about the pulley 14 does not always occur.

To effect the carriage returnoperation, mechanism is provided fordisengaging, and holding disengaged, the feed pawl 18 and thedetent pawl84 which is pivotally mounted on stud 85 on the side plate L2. Thedetent pawl 34 is normally biased into cooperation with the teeth oi theratchetgwheel H by a spring 86. Having reference, to Fig. 2, the shaft29. is provided at;its end adjacenttotheinner face of the side plate l2with a pin 9i for-controlling the carriage return operation. Pivotallycarried on pivot 92 secured to a bracket 93-fixed to the printing bail41 is a lever 94, the lower end of which is conformed to cooperate withthe pin. 9! inabuttin-g relation under certain operating conditions in-'dicative ofthecarriag return function. The upper end of lever 94 haspivotal articulation with a stud 95 which extends through. an aperture961 in the side plate l2, and-is fixed to the upper end of a trip lever91 pivoted on a stud 98- afiixedto the outer side of side plate l2 (Fig.5). The lower end oflever 91 is adapted to have latching relationshipwith a shoulder 99 formedona lever HM, whichis ivoted on the common.pivot stud 8! on which the bell. crank 'H-isalso pivotally mounted.-Lever IiH isnor mally biased in a counterclockwisedirection by aspringH32 distended between. the extremity of lever l'lll andla stud Hi3 fixedto the side plate. l2.

As the carriage spacing mechanism comprising the pulley it operates tomove the type wheel 27- fromcthe side plate H to theside plate !2; acar-- riage return spring I'M is tensioned. One end ofv the carriagereturn spring IE4 is anchored at N35 to the sideplata L2,. and totheother end ofthe carriage returnspring Hi4 there is fastened one end of acable lil5-,-the other endof which is adapted to be wound around the hubin? of a wheel-and-axle arrangement I08 rotatably mounted at H19 (Fig-.-4') on the side plate I I-.- Securedto the sheave portion of the wheeland axlemechanism I081. is one end of a cable Ill. (Fig.- 4) which isadapted-to be woundaround thesheave portion oi pulley Hi8; and whichextends; as shown in Fig. 4, around a smallpulley H-Z positioned.- in anaperture- H3 in the side plate I], whereby the-cable IH- passes throughthe side plate l-I andlis attached to the U-shaped' bracket 63 whichcarries the type wheel 21-.- As the; type-wheel mechanism is steppedaalong the shaft 29 trom side plate H to side plate l2 by the. characterspacing. mechanism through the instrumentality of pawl 78' and ratchet11, the spring I04" is tensioned by causing the cable li t to be unwoundfrom: the sheave portionof the wheel: and axle mechanism t08 and thecable Hi6 to be wound: upon the-hub portionv I01 thereof, With thecarriagereturn arrangementshown; the cable Wit-moves substantiallyone-third the dis tance that thecable T I moves for each characterspacing, operation thus providing a very compact tensioning arrangement.

To achieve the carriage return operation the carriage return signal isreceived by the selecting magnet 32 and is :oil suchnaturethat, havingref-'-- erence; to Fig. 1, the: portion A of the signal (which is theportion ofspacing nature)- is 0t short duration, as is exemplified bythe relative position between. the-pin 9| and thelower endoi the-lever94in Fig. 2c The'angular'positionnient between these two elementsindicates that between the initiation ofrotation of shaft 29 andtheinstant ofregistry of the pi'n 94 withthe lower end of lever. 94, ashort time interval. has elapsed whereuponv the marking portion of thecode-sig nal isimpressed on the signal line to energize the magnet 31..Normally, for ordinary cl iaracterv printing operations, upon theenergization of magnet 3| in; response tothe marking: portion of thecode signal, as shown inFig- 1,.theenergiza tion of. the selectormagnet- 3l will cause the operation of thearmature lever 33 in aclockwise direction (as viewed in Fig. 4) to cause, through the printcontrol lever 43, the actuation of the printing bail 41 counterclockwise(as viewed in Fig. 2), and the lever 94 is caused to rotate about thefulcrum pin 95. However, during the carriage return operation, themarking portion of the signal is received when the pin 9I is in registryor blocking relation with the lower end of the lever 94 so that when theprinting bail 41 is actuated by the print control lever 43 the lower endof lever 94 abuts the pin 9| and causes the lever 94 to rotate about thepin 9! as the fulcrum thereby imparts motion to the fulcrum pin 95 whichis fixed to the lever 91, and hence the lever 91 is caused to rotateabout its fulcrum 98 in a counterclockwise direction (as viewed in Fig.5) against the action of its spring II2 to cause the bottom end of thelever 91 to become disengaged from the shoulder 99 from lever IBI. LeverIOI is now free to respond to the urge of its spring I02 and is therebyrotated in a counterclockwise direction. Pivotally connected to leverIUI and depending therefrom is a pawl arm I I3 which is normally biasedin a counterclockwise direction by a spring II4 extending between thelever H3 and the extremity lever of IIII. Lever I I3 is provided on theside confronting the side plate I2 with a stud I I which cooperates withthe detent pawl 84 so that when the lever IOI is permitted, through thedisengagement of the lever 91 from the shoulder 99, to respond to thepull of its string I02, this movement is imparted to the lever II3which, through stud I I9, imparts clockwise rotation to lever 84 againstthe action of spring 86, thereby releasing the detent pawl 84 from theratchet wheel 11. The free end of the pawl arm 84 cooperates with anoverhanging projection I I5 integral with the feed pawl 18.

When the pawl 84 is raised by the stud IIiI, its end will cooperate withthe end II5 of lever 18 to disengage the pawl 18 also from the ratchetwheel 11. The pulley 14 is now free to respond to the pull of thecarriage return spring I04, which by rotating the wheel and axlearrangement I98 causes the cableI II to be wound upon the sheave portionof the arrangement I88 while the cable I 06 is unwound therefrom. Inthis manner the tpye wheel actuating bracket 83 is caused to be movedfrom the side plate I2 to the other side plate II, thereby unwinding thecable II from the pulley 14. To maintain the pawls 18 and 84 in theirdisengaged position during the carriage return operation, a laterallydisposed lug or projection H6 is provided on the detent pawl 84. As theratchet wheel 11 is rotated during carriage spacing operations, a studII1 carried thereon is also caused to move therewith so that it movesaway from the lever II8 pivoted at II9 to the side plate I2 (Fig. 5). Asthis occurs, spring I2I causes lever II8 to be biased counterclockwiseto bring its extremity to bear against the lug II6 of the detent pawl84. Now, as the stud II1 recedes from the lever H8, and the lever 84 israised by the stud Hi], the lever I I8 through its shouldered extremityacts to hold. through the projection II6, the lever 84 latched againstdownward movement by its spring 86. In this manner, the pawl arms 18 and84 are held disengaged from the ratchet wheel 11 during the carriagereturn operation. However, at the completion of the carriage returnoperation, the pin or stud I I1 on the ratchet wheel 11 returns to itsposition adjacent the lever H8 and is stopped thereat by the hookportion I22 of said lever I I8.

The inside surface I23 of hook portion I22 is so contoured as to cause abudging action between the stud H1 and the lever II8 to impart a slightclockwise motion to the lever II8 against the action of spring I2I toinsure the disengagement of the shouldered extremity of lever I I8 fromthe lateral portion IIB whereupon the spacing pawl 18 is returned intoengagement with the teeth of the ratchet wheel 11 by spring 83, and thedetent pawl 84 is returned into engagement with the teeth of the ratchetwheel 11 by spring 86. The beginning-of-line condition of the printingmechanism is as shown in Fig. 5.

The lower end of the line feed pawl H3 is proided with a hooked portionI24 and a lateral guiding portion I25. The hooked portion I24 cooperateswith a, ratchet wheel I26 fixed to shaft I21 journaled in the sideplates II and I2. The ratchet I26 is fixed to the shaft I21, and alsofixed to the shaft I21 and disposed between the side plates II and I2 isa guide roller I28, Figs. 4 and 6. The guide portion I of the line feedpawl I I3 cooperates with the guide member I23 (see Fig. 3) secured tothe side plate I2. A jockey roller I3I is mounted on a spring I32fastened to a bracket I33 secured to the side plate I2 whereby the linefeed ratchet I25 is held or detained in its operated position. The sideplates II and I2 are provided with bearings for a shaft I34 whichcarries a paper roll I35 (Figs. 3, 5, and 6) on which a paper web rollI36 is carried. Cooperating with the guide roller I28 are a pair ofpressure rollers I31 located one at each extremity of the roller I28.Pressure rollers I31 are carried on suitably supported brackets I38 andare spring biased by spring I39 against the guide roller I28. The paperI36 is passed around the chute I 4| and thence between the pressurerollers I31 and guide roller I28 and up along the guide I42 through theprinting zone between the printing bail 41 and the spring member 66,thence out of the printing mechanism. Thus, during each carriage returnoperation, the line feed operation is performed simultaneously, sinceupon the upward motion of the pawl I I 3 not only are the detents 18 and84 disengaged from the ratchet wheel 11, but also, the line feed ratchetI26 is operated by the pawl II3 to efiect a line spacing or feedingoperation of the paper web I38 from the roll I35.

The cam 28 not only spans the bell crank 19, but also is wide enough toact upon the lever IIlI so that at the completion of the revolution ofcam 28, said cam will operate upon a shoulder portion I43 of lever Ifllto depress the lever IGI, or rotate it clockwise against the action ofits spring I02 to permit the reengagement or latching of the lever 91with the shouldered portion 99 of lever IOI, whereat the lever I0! isheld until a subsequent carriage return signal is received. The shaftI21, as shown in Fig. 3, is extended beyond the side plate I2 andcarries at its extremity a hand wheel I44 for manual line feedingoperations.

General operation Before beginning operation of the printing apparatusherein shown, the orientation index pointer 54 is manipulated so thatthe stop lug 56 of lever 52 is properly adjusted to efiect substantialsynchronization with the received signals, after which the index arm 54is properly clamped in place. The normal operating condition of the lineis a marking or current condition whereby the selector magnet 3| remainsenergized, and the stop lug 56 is presented into the path of the stoplug 51 thereby holding the type wheel shaft 29 quiescentwhile the gear22 constantly rotates. It is assumed that the type wheel 21 ispositioned at the beginning-of-line position preparatory to printing a,new line.

Due to the nature of the isochronous code sig nal employed incontrolling the operation'ofthe printer according tothe presentinvention, the commencement of the start impulse causes the selectormagnet 3'I to be de-energized andlper mits spring 3| to actuate thearmature lever33 to its counterclockwise position against. the stop 32,but in response to thismovement of arma= ture lever 33, stop lever 52 isremoved by its spring 58 from engagement withhstop lugil, permitting theshaft 29 and theelements controlled thereby to rotate.

By this action of armature lever 33, the pawl 36- is moved intoengagement with the next tooth on the printing cam 31. At an instant inthe cycle of rotation of shaft 29 determined by the particular characterto be printed and evidenced by a reversal of the current in the line,the magnet 3| becomes energized and instantly effects the movement orattraction of its armature lever 33, thuscausing, due to the action ofpawl: 36 upon printing cam 37! and consequently the action of cam 3!upon print control lever-43, and in turn the action of the lever #3 uponthe stud 48-, the printing bail 31 to swing toward the type wheel 2 andpress the page material I36- against the character. selected. Theprojection 46 on the print control lever 43 acts-on the indexing wheel24- to arrest the type wheel momentarily from rotation. While the shaft29 is thus rotating, the cam 28 is also operating andtoward the end ofthe cycleof rotation, cam 23 operates upon bell crank lever 19 torotate, through feed pawl I8, the ratchet wheel "IT to effect character,spacing, in the ,manne'rflpre viously described.

This procedure continues until the carriage return signal is received,whereupon in response to the carriage return signal the magnet 31' isfirst de-energized momentarily, causing the type wheelshaft 29 to rotateas previously described, and thereafter causing the selector magnet'3lto be again energized upon a reversal of current in'the lineatthe=-instant when pin 9| is in registry or blocking relation with thelower end of lever 94. The energization of magnet 3I at this timecauses, through lever 43, the operation of the print bail 4'! and hencelever 94 to cause lever 94 to rotate clockwise about its pivot 92 toswing the latch lever 9'! out of latching relation with lever IllI,thereby permitting spring I02 to operate lever IUI to raise the linefeed pawl H3, and through stud III] raise the detent lever 8.5 and feedpawl 18 out of engagement with the character spacing ratchet 'I'Ithereby permitting the ratchet IT to rotate in a counterclockwisedirection until the stud II'I thereon strikes against the hooked portionI22 to release or disengage the lever H8 from the portion H6 and in themeantime concurrently with the carriage return operation, the pawl II3operates to rotate the line feed ratchet I26 clockwise (as viewed inFig. to efiect the line feeding operation, after which the printingapparatus is in position for another line of printing.

What is claimed is:

1. In a telegraph page printer, a start-stop shaft, a type wheel carriedthereon, means responsive to the first portion of a received signal forstarting rotation of saids'liaft and responsive to the second portion ofsaid signal for i'estorring stop conditions tdtikidslieift, means foradvaneirigsaia type wheeialorigsaid shaft to ro= diio character-paes,...and a printing bail, co"- extensive with the total movement ofsaid type wheelon saieshaft, operablepy said first means in response tosaid second portion of said receivd signer 2:11: a telegraphpage-printer, astart-s'top short, a cam printing means, asingie magnetresponsive to equal length code signals, each signal comprisingsir-start Go'fiditipnafid a Stop condition or complementary periodiclengths, means to perform character spacing,- and means resprmsive tothe start condition of asignal for initiating rotation ofsaid shaft andsimul taneously preparing said'printing means for of festive-operation,- and subsequently responsive to the transition from start tostopvconditionlto effect initially the camming .of-saidt rintmgIiiasHSySEGGllidl-Y operation of said character spacing means andsubsequently; the ar'iestment of said shaft.

3i In: a telegraph page printer responsive to isochronou's nronopu lsecode: signals comprising arr initial portionanda definitive portion-astarts-stop" shaft, aatyp'e wheel carried thereon, aprinting :ba-i'l,means responsive to: the initial portion of said signals to release.said: shaft for rotationto: condition said typewheel to. performprinting operations, means effective upon the transition fromsaiciinitia pa ties-to th efinitive-sort n lo saideeiena t ene a e's ito consummate "the pr ntin ope at on s ac hanism fo am ss n sai typewhee alone a dsh t'te prod e-ch racte ;sp es; d, ans carried bysaidshaft effective in response to said release of said shaft andsubsequent-topaid printingloperationto effect the operationlof; saidspacing mechanism.

4.311% 3; pager-printer; asir rgle magnet responsive -toequal lengthcode signals, each signal comprising a firstconditionand a: secondc"on.- dition ,of corriplementary, peribdiollengths, pawl and ratchetprinting means, indexing means for said printing means responsive tosaid firsmorrdi'tion ror'pre par g. for action, rhfelir'isie fifctiv' vfrom said first to" said second condition to" earn said printing meansto effect, under the control of said indexing means, the printingoperation, means to form character spaces operative as an incident tothe printing operation, and carriage return means directly controlled bysaid printing means.

5. In a telegraph page printer, a start-stop shaft, a cam printingmeans, a single magnet responsive to equal length code signals, eachsignal comprising a start condition and a stop condition ofcomplementary periodic lengths, means to perform character spacing,means responsive to the start condition of a signal for initiating therotation of said shaft and simultaneously preparing said printing meansfor effective operation, and subsequently responsive to the transitionfrom start to stop condition to effect initially the camming of saidprinting means, secondly the operation of said character spacing meansand subsequently the arrestment of said shaft, a first instrumentalityassociated with said printing means, a second instrumentality associatedwith said start-stop shaft, carriage return means, and means efiectiveunder certain predetermined operating conditions through the 00-operation of said instrumentalities to enable the operation of saidcarriage return means.

6. In a telegraph printer, a start-stop shaft, a cam printing means, asingle magnet responsive to equal length code signals, each signalcomprising a start condition and a stop condition of complementaryperiodic lengths, means to perform character spacing, means responsiveto the start condition of a signal for initiating the rotation of saidshaft and simultaneously preparing said printing means for effectiveoperation, and subsequently responsive to the transition from start tostop condition to effect initially the camming of said printing means,secondly the operation of said character spacing means and subsequentlythe arrestment of said shaft, a carriage return control instrumentality,a sensing member pivotally carried by said printing means andarticulated to said instrumentality, a fulcrum member associated withsaid start-stop shaft, and carriage return means effective under certainpredetermined operating conditions through the cooperation of saidsensing member and said instrumentality.

'7. In a telegraph printer, a start-stop shaft, a printing means, asingle magnet selecting means responsive to monopulse code signals toselect a character to be printed, character spacing means, meanscontrolled by said selecting means to effect sequentially the initiationof said shaft for rotation, the operation of said printing means, theoperation of said spacing means and the arrestment of said shaft, acarriage return control instrumentality, a sensing member pivotallycarried by said printing means and articulated tosaid instrumentality, afulcrum member associated with said start-stop shaft, and carriagereturn means effective under certain predetermined operating conditionsthrough the cooperation of said sensing member and said instrumentality.

8. In a telegraph printer, a start-stop shaft, a printing means, asingle magnet selecting means responsive to monopulse code signals toselect a character to be printed, character spacing means, meanscontrolled by said selecting means to govern sequentially the initiationof said shaft for rotation, the operation of said printing means, theoperation of said spacing means and the arrestment of said shaft, acarriage return control instrumentality, a sensing member pivotaliycarried by said printing means and articulated to said instrumentality,a fulcrum member associated with said start-stop shaft, carriage returnmeans effective under certain predetermined operating conditions throughthe cooperation of said sensing member and said instrumentality, detentmeans for facilitating the completion of operation of said carriagereturn means, and cam means associated with said detent means forcontrolling the restoration of said carriage return means to itsoperative condition.

9. In a telegraph page printer, a start-stop shaft, means responsive tothe first portion of a received signal for starting rotation of saidshaft and responsive to the second portion of said signal for restoringstop conditions to said shaft, a type wheel, means for advancing saidtype wheel along said shaft to produce character spaces, carriage returnmeans, a printing bail, coextensive with the total movement of said typeWheel on said shaft, operable by said first means in response to saidsecond portion of said received signal, a first instrumentalityassociated with said printing means, a second instrumentality associatedwith said start-stop shaft, and means effective under certainpredetermined operating conditions through the cooperation of saidinstrumentalities to enable the operation of said carriage return means.

10. In a telegraph page printer responsive to isochronous monopulse codesignals comprising an initial portion and a definitive portion, printingmeans including a typing instrumentality, means responsive to theinitial portion of said signals to initiate operation of said printingmeans, means effective upon the transition from said initial portion tothe definitive portion of said signal to consummate the operation ofsaid printing means, spacing mechanism, means to operate said spacingmechanism to effect character spacing movement of said instrumentality,and means effective in response to said initiation of operation of saidprinting means and subsequent to said consummation of operation of saidprinting means to effect the operation of said spacing mechanismoperating means.

WALTER J. ZENNER.

